https://www.selleckchem.com/products/hs-10296.html There are currently three anti-interleukin-5 (IL-5) pathway-directed therapies mepolizumab, reslizumab, and benralizumab. Of these, benralizumab was most recently approved. Benralizumab is administered every 8weeks after an initial 3 doses given every 4weeks, whereas mepolizumab and reslizumab are administered every 4weeks. This convenience in benralizumab administration indicates that it is potentially beneficial for patients. Therefore, we potentially have an opportunity to change to benralizumab in patients who responded to mepolizumab or reslizumab. However, other than eosinophil levels, factors that could predict patients responding to anti-IL-5 pathway-directed therapies have been unknown. In this study, we examine the clinical characteristics of mepolizumab responders who achieved successful switching to benralizumab. A total of 18 consecutive severe asthmatic patients treated with sequential mepolizumab and benralizumab, each for at least 1year, were enrolled in this study. This study was a single-center case series. Patients were defined as having achieved successful switching to benralizumab if they satisfied either of the following for 1year before and after the benralizumab treatment (1) they experienced no exacerbation; or (2) they experienced no exacerbation and discontinued oral corticosteroids. All 18 patients responded to mepolizumab treatment, and 11 of them achieved successful switching to benralizumab. The proportion of patients who achieved successful switching to benralizumab was higher in patients with eosinophilic chronic rhinosinusitis (ECRS) than in those without (76.9 vs. 20.0%; p=0.025). Our findings imply that in responders to mepolizumab, there may be a higher response rate to benralizumab in patients with ECRS than in those without. Our findings imply that in responders to mepolizumab, there may be a higher response rate to benralizumab in patients with ECRS than in those without. Very